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The processes of formation of a thin film of cobalt disilicide on the silicon surface due to the formation of several nuclei of atomic thickness on the surface of the silicon substrate are presented. To create these structures, the ion implantation method was used. The dependence of the depth of penetration of ions into the substrate during ion implantation on temperature and ion dose was determined. In the case of implantation of Co+ ions into Si at room temperature silicon uniformly combines with Co atoms at a depth of 3.5–4 nm, the Co concentration in these layers is 45–50 at. %. Co has been shown to form chemical bonds with Si atoms in the sample containing 40–45 atomic % of Co. When implanting Co+ into Si at 600 K, it was found that the depth of the same added layer is 2.5–3 nm, and CCo forming bonds with Si atoms increases to 85–90%. [ABSTRACT FROM AUTHOR]

The processes of formation of a thin film of cobalt disilicide on the silicon surface due to the formation of several nuclei of atomic thickness on the surface of the silicon substrate are presented. To create these structures, the ion implantation method was used. The dependence of the depth of penetration of ions into the substrate during ion implantation on temperature and ion dose was determined. In the case of implantation of Co+ ions into Si at room temperature silicon uniformly combines with Co atoms at a depth of 3.5–4 nm, the Co concentration in these layers is 45–50 at. %. Co has been shown to form chemical bonds with Si atoms in the sample containing 40–45 atomic % of Co. When implanting Co+ into Si at 600 K, it was found that the depth of the same added layer is 2.5–3 nm, and CCo forming bonds with Si atoms increases to 85–90%. [ABSTRACT FROM AUTHOR]

Thin films of CrSi2 of various thicknesses, deposited on the Si(111) surface using magnetron sputtering, have been examined through a combination of electron spectroscopy and microscopy techniques. In this article, the mechanism of film formation by sputtering in very short times by the method of magnetron sputtering was studied. In addition, the electrophysical and thermoelectric properties of the formed film were studied for the first time in the article. For the first time, the composition, surface morphology, and cross-section of the thin films, as well as the temperature dependences of the resistivity, Seebeck coefficient, and power factor have been investigated. In the article, a SiO2 substrate on the Si(111) surface was used to form a CrSi2 film. This substrate was chosen due to its temperature resistance and good dielectric properties. The following articles provide information on weekubstrates for growing structures, their formation, and thermoelectric properties (Noroozi et al. in ECS J Solid State Sci, 6:Q114, 2017; Muhammad et al. in Chem Papers, 77:6533–6542, 2023; Alhadhrami et al. in J Taibah Univ Sci, 17:2236368, 2023). It is proven that an amorphous CrSi2 film entirely covers the SiO2/Si(111) surface, starting at a thickness of ~ 400 Å (deposition time ~ 60 s). A homogeneous polycrystalline CrSi2/SiO2/Si(111) film is created after heating the CrSi2/SiO2/Si(111) system to a temperature of approximately 750 K. It is demonstrated that for a CrSi2/SiO2/Si(111) film with varying thicknesses (80 and 180 nm), the resistivity ρ, the power factor P, and the Seebeck coefficient S change nonlinearly with increasing temperature. For CrSi2 films with varying thicknesses, their values are marginally different from one another. In particular, it was found that with increasing T, the resistivity ρ of the polycrystalline film decreases, while the Seebeck coefficient S increases. It is demonstrated that the excitation of electrons from hybridized 3p levels of Si and 4 s and 3d levels of Cr results in three peaks in the photoelectron spectrum. [ABSTRACT FROM AUTHOR]

The characteristics of existing temperature sensors based on silicon monocrystals are analyzed, and the reasons for the limited upper limit of temperature measurement are established. To increase sensitivity, expand the range of measured temperatures, and obtain a linear output characteristic of the temperature sensor, the authors propose to carry out phased implantation of P+ and B+ ions with decreasing energy in different directions of the Si(111) crystal followed by brief thermal, laser or IR radiation after each stage ion implantation. The distribution profiles of P and B atoms implanted into Si with a gradual decrease in energy are studied. The effect of subsequent thermal and IR annealing on the atomic distribution profiles and the characteristics of a thermal sensor was investigated. A p-i-n diode with a high concentration of electrically active atoms (NP=1021 cm-3, NB=2·1021 cm-3), with almost a step distribution of P and B atoms and a sharp boundary p-i and i-n was created areas with a high thermal sensitivity of 2.3 mV/K in a wide temperature range of 20-550 K.

Studies of Mn4Si7 coatings of different thicknesses have shown that magnetron deposition practically does not change the composition of the coating in comparison with the composition of the target. The technology and basic modes of creating the necessary targets for a magnetron sputtering device are presented. Targets were created by adding silicon and manganese powders in the required amount and heating them under vacuum conditions at high temperature and pressure. Thin silicide films (coatings) of different thicknesses were formed on the surface of silicon dioxide from the produced targets using the method of magnetron sputtering. Studies of the transmission, absorption, and reflection coefficients of coatings in the visible region of the spectrum have shown that for the Mn4Si7 coating, the reflection coefficient is practically the same at all wavelengths. It was found that the Seebeck coefficient varies from 16 µV/K to 22 µV/K, and the resistance decreases from 77 Ω to 20 Ω with increasing thickness of the thin Mn4Si7 coating. [ABSTRACT FROM AUTHOR]

The results of complex experimental studies of the parameters of thin coatings of SiO2 oxides on Si, formed by thermal oxidation at temperatures of 1200 °C, including studies using electron and X-ray spectroscopy, IR-Fourier spectrometer IRTracer-100 - developed by Shimadzu, Raman scattering, and test electrophysical structures, are presented. Data have been obtained that for a silicon dioxide thickness of about 400 nm, the porosity of the coating does not exceed 2/cm2, and the electric field strength for the breakdown of the dioxide reaches 5·106 V/cm. The crystal structure of SiO2 is triclinic, lattice period a = 4.9160 Å, b = 4.9170 Å, c = 5.4070 Å, a = 90.000, b = 90.000, γ = 120.000, density 2.64 g/cm³. [ABSTRACT FROM AUTHOR]

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Copyright of Journal of Polytechnic is the property of Journal of Polytechnic and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The paper presents the results of comprehensive study of SiC samples, which is one of the most promising materials in the field of semiconductor nanotechnology. The identification and qualitative analysis of a SiC sample was carried out by Raman spectroscopy using an In Via Raman spectrometer. Based on the spectrogram of X-ray phase analysis, the amorphous and crystalline phases of this substance were determined. At the same time, according to the peaks of the spectrogram, based on the Miller indices and inter planar distances dhkl, complex compounds are shown that are newly formed on the basis of silicon carbide. Using the method of IR spectroscopy, the IR spectra of SiC were obtained in the optical range ν = 400-4000 cm−1. [ABSTRACT FROM AUTHOR]

The regularities of the formation of thin Mn/Si (111) nanofilms during solid-phase deposition of Mn on Si under conditions of ultrahigh vacuum (P = 1 0 − 7 Pa) and thin Mn4Si7/Si (111) nanofilms during annealing of the Mn/Si system have been studied. It has been established that silicon atoms diffuse into the Mn film up to a thickness of Θ = 1 0 –12 monolayers, and Mn in Si up to Θ = 8 –10 monolayers, therefore, a transition layer of nonstoichiometric MnxSiy silicide is formed at the Mn–Si interface. After heating at T = 1 0 5 0 K, the higher manganese silicide (HMS) Mn4Si7 is formed. In particular, it was found that the bandgap of Mn4Si7is E g ≈ 0. 7 2 eV, and the electron affinity is χ ≈ 3 eV and in the work, the optimal thermal diffusion conditions for the formation of stoichiometric Mn4Si7 silicide are determined. It is shown that at T ≤ 1 0 0 0 K, a partial formation of a chemical bond between manganese and silicon atoms occurs. At 1100 K, a thin Mn4Si7 film with a good stoichiometric composition is formed. [ABSTRACT FROM AUTHOR]

There arises the formation of thin films of cobalt monosilicide (CoSi) deposited into the base surface of SiO2/Si (111) using magnetron ion-plasma sputtering and subsequent thermal annealing. It was found that, in addition to the formation of CoSi silicide, also there are Co and Si atoms that do not form bonds on the surface. Therefore, in this work, we studied the surface morphology and composition of a CoSi silicon target using a scanning electron microscope. The study, silicide CoSi, was chosen as the target and standard SiO2/Si (111) was used as the substrate. The surface morphology and composition of the CoSi silicon film obtained by scanning electron microscopy had been studied. The paper reports on a method, morphology of the surface of a CoSi silicon film obtained using Raman microscopy. The results obtained are based on the fact that they were obtained using a modern magnetron sputterer, a high-vacuum thermal heater and modern devices. [ABSTRACT FROM AUTHOR]

Using the methods of ultraviolet photoelectron spectroscopy, light absorption spectroscopy, and true secondary electrons, the effects of deposition of Cs atoms with a thickness of 1 monolayer on the density of electronic states in the valence and conduction bands, energy band parameters, and quantum yield of photoelectrons have been studied for the first time. It has been established that when cesium is deposited on the surface of cobalt disilicide with a thickness of 1 monolayer, the value of Еg and the positions of the maxima of the density of states of valence electrons practically do not change, the work function of photoelectrons decreases to 3 eV, and the quantum yield of photoelectrons increases by a factor of 3 or more. After deposition of Cs on the surface of CoSi2/Si (111) with a thickness of d 500 Å, the yield of true secondary electrons into vacuum increases, and the beginning of the spectrum shifts towards lower energies by ~ 2.4 eV, i.e., the potential barrier (electron affinity ) decreases by 2.4 eV. The decrease in Ф is mainly due to the decrease in the width of the conduction band . In this work, for the first time, the positions of the maxima of the density of free electron states in the conduction band of CoSi2 are experimentally determined. It is shown that the maxima are located at energies of 0.8 and 1.9 eV below the vacuum level. [ABSTRACT FROM AUTHOR]

The processes of formation of a thin film of cobalt disilicide on the silicon surface due to the formation of several nuclei of atomic thickness on the surface of the silicon substrate are presented. To create these structures, the ion implantation method was used. The dependence of the depth of penetration of ions into the substrate during ion implantation on temperature and ion dose was determined. In the case of implantation of Co+ ions into Si at room temperature silicon uniformly combines with Co atoms at a depth of 3.5–4 nm, the Co concentration in these layers is 45–50 at. %. Co has been shown to form chemical bonds with Si atoms in the sample containing 40–45 atomic % of Co. When implanting Co+ into Si at 600 K, it was found that the depth of the same added layer is 2.5–3 nm, and CCo forming bonds with Si atoms increases to 85–90%. [ABSTRACT FROM AUTHOR]